Solidified gas refrigerator



Oct. 2, 1934.

s. T. sl- IERRICK .SOLIDIFIED GAS REFRIGERATOR Filed Aug. 29. 1932 2Sheets-Sheet l INVENTOR OGL 2, 1934 s'. T. sHERRlcK SvOLIDIFIED GASREFRIGERATOR Filed Aug. 29, '1952 v 2' shams-sheeru 2' INVENToR I.54mm-z Z' @MWF/cf( BY g ATTORNEY Patented Oct. 2, 1934 UNITED STATESPATENT OFFICE;

This invention relatesv to means for employing solidied gas, such assolidified carbon dioxide, for use as a refrigerant in railroadrefrigerator cars.

5 The principal object of the invention is to provide a container forthe solidified gas which will be unusually eilicient in heat absorption,and yet which will be very economical in the use of the solidified gas.

Another object of the inventionis to so construct the container thatportions of the walls thereof will be brought to an exceedingly lowtemperature so as to chill and circulate the surrounding air.

Still another object of this invention is to so construct the containerthat it will have a maximum area of cold surface in comparison to itssize that a relatively small container will cool a relatively largevolume of air.

A further object is to construct a container which can be fitted throughthe present ice hatch doors of refrigerator carsv so that no change ofany nature will be -required in the car, 'and so that, should solidifiedgas be unobtainable, the container may be instantly replaced with waterice. I

Other objects land advantages reside in the detail construction of theinvention, which is designed for simplicity, economy, and efficiency.

These will become more apparent from the following description.

In the following detailed description of the invention reference is hadto the accompanying drawings which form a part hereof. Like numeralsrefer to like parts in all views of the drawings and throughout thedescription.

In the drawings:

Fig. l illustrates a fragmentary, longitudinal section through a typicalrailroad refrigerator car with the invention in place therein.

Fig. 2 is a cross sectionthrough the ice bunker of the car taken on theline 2-2, Fig. 1.

Figs. 3, 4, and 5 illustrate vertical sections through alternate formsof the invention.

`In the drawings the refrigerator car is designated in its entirety bythe numeral 10. The car 10 is provided with ice bunkers 11 at itsextremities, within which, ice supporting racks 12 are positioned. Eachof the bunkers ll hasv a bottom grill 13 for the exit of the cooled airand a top grill 14 for the entrance ofthe heated air.

Each of the bunkers 1l is provided with two hatchways 15 through whichthe bunkers are 55. normally iced. These hatchways are provided vwardlywithin the hatchway l5. The upper excoarse wire or rod screen withinclined paces against which a relatively thick hatch cover 16 fits.

The invention comprises a sheet metal container 17 of a convenient sizeto be slid down- 60 tremity of the container l0 is flared outwardly asshown at 18 to rest against the inclined inner faces of the hatchway 15.The hatch cover 16 will be received into the inclined top of thecontainer 17 to close the latter and to lock it into 55 place in thehatchway. The entire container may be supported by the flange likeaction of the flared vtop 18. When the cover 16 is closed it acts toclamp the are top to the hatchway sides so that it cannot becomeloosened therefrom. 70

It is preferred to vform the lower extremity of the container 17 into aseries of two or more legs 19. As illustrated the container is providedwith two legs 19, but it may be provided with any desired number oflegs. A sub-floor 20 is 75 positioned across the container 17immediately above` the legs 19. This sub-floor may be formed in anydesired manner so that it will be open for the circulation of gas orair. i One method of forming the sub-floor is to place a relatively 30or grill across the container.

The inner faces of the walls of the container 17 are provided withsuitable heat insulation 21. This insulation, however, does not coverthe entire inner surface of the walls. For instance it is preferred toterminate the insulation at the subfloor 20 so as to leave the innersurfaces of the legs 19 bare, and to also terminate the insulation belowthe top of the container 17 so as to 90 leave an upper bare portion 22.In other words the walls immediately around the solidified gas 23 willbe insulated but the walls above and below the position` of thesolidified gas will be bare or noninsulated.

In use, solidified gas is placed in the container 10 so as to rest uponthe sub-floor 20. Asvthe solidified gas vaporizes, the interior of thecontainer 17 will eventually become entirely filled with cold vaporizedgas. Means must be provided for allowing this gas to escape, as furthervaporization will create a pressure within the container.

It is not usually desirable to have this gas escape into the car as ithas a decolorizing and injurious effect on some foods. As illustrated, agas outlet pipe 24 is extended through the hatch cover 16 and providedwith a suitable check valve 25. The pressure of the gas in the containerwill open the check valve and allow the gas to escape to the atmosphereoutside the refrigerator car 10.

-exceedingly cold legs thereof.

The gas within the container 17 circulates by convection, that is, thecolder gas moves downwardly into the legs 19 and, as it absorbs heat,moves upwardly into the upper portion of the container where a part ofit will escape through the check valve 25. Another part will be chilledby its second contact with the vaporizing solidified gas, and will againfall into the legs 19. This constant circulation of exceedingly cold gaswill bring the outer surface of the legs 19 to an exceedingly lowtemperature, especially since the legs are bare and devoid ofinsulation.

Within the car 10, the warm air will rise to the roof and then flowthrough the gratings 14 into the ice bunkers 11 there to be chilled byits contact with the exceedingly cold walls of the container, andespecially by its contact with the This cold dense air will settle tothe bottoms of the bunkers and then flow through the gratings 13 tochill and refrigerate the car contents.

It is desired to call particular attention to the upper bare surface 22which is also devoid of insulation. The air entering the bunker throughthe grill 14 will immediately strike this cool surface which will act toinstantly condense it and start it on its downward path through thebunkers. It has been found that the upper bare surfaces 22 quicklyincrease the circulation through the bunkers as they overcome theinitial inertia of the incoming warm air.

It is preferred to form handle loops 26 on the interior of the container17, to which crane hooks may be attached for removing the containersfrom, or replacing them in, the cars.

In Fig. 3 an alternate form of the invention is illustrated. In thisform, the insulation comprises sectional insulating panels 26 which aremaintained against the walls of the container by means of suitableguides 27. 'Ihe panels 26 are not secured vto the walls, but areslidable thereon, so that the may be moved or removed to expose eithermore or less bare wall or to position the bare portions thereof eitherat the bottom or at the top as desired. They may be placed apart toprovide a series of bare spaces throughout the wall area if desired.This adjustable panel feature provides a. minute control of the cartemperature if the contents are such that a very low temperature isdesired, more of the sectional panels may be removed to expose a largerarea of heat absorption surface. This brings the air in the bunkers to alower temperature and cools a larger volume thereof. If the contents donot require such excessive cold additional panels 26 may be inserted.

In Fig. 4 a second alternate form is illustrated for use where anexcessively low temperature is not desired. In this form the legs of thecontainer are partially insulated by means of strips 28 of insulatingmaterial spaced apart along the legs. These strips of course, limit thecold area of the legs and naturally reduce the amount of heattransferred from the car interior to the solidied gas. This results in ahigher car temperature and less consumption of the gas.

In Fig. 5 still another form is illustrated, more particularly designedwhere an exceedingly low temperature and exceedingly rapid exchange ofheat to the refrigerant. In this form the legs are bare and providedwith metallic absorbing vanes 29 which are secured to or formed on themetallic surfaces of the container. 'I'hese vanes greatly increase theheat absorption area of the container and the heat they absorb istransferred to the container walls thence to the cold interior gas andthence to the refrigerant. Any desired number of the vanes may beemployed and they may be extended any desired distance along thecontainer. In this `form the insulation about the refrigerant has beenreduced to a minimum by forming openings or passages 30 therethrough toallow the heat to be absorbed from spaced apart areas on the outerwalls.

While several forms of the invention have beenillustrated and describedthey all carry out the same basic idea of transferring the heat througha metallic membrane or wall from the car interior to the refrigerant sothat the cold metallic wall will occupy the position of and functionsimilarly to the surface of the water ice originally used in therefrigerator car, and to provide means for controlling this cold surfaceso as to increase or decrease its active area according to thetemperature desired.

While a specific form of the improvement has been described andillustrated herein, it is desired to be understood that the same may bevaried within the scope of the appended claims, without departing fromthe spirit of the invention.

Having thus described the invention, what is claimed and desired securedby Letters Patent is:

l. A refrigerating container for solidified carbon dioxide comprising: acontainer for said material; hollow legs formed in the bottom of saidcontainer; a screen member separating said legs from the containerproper; insulating material covering the inner walls of said container,said insulating material terminating at said screen so as to leave saidlegs uninsulated; a cover for said container; and a gas escape ventthrough said cover.

2. A solidied gas refrigerator comprising: the combination of a metalcontainer for said solidied gas; a shelf with openings through it tosupport said solidified gas; heat insulating material laterallysurrounding the zone in which the solidiiied gas reposes; hollow legsformed in the lower portion of said container; means for ventingvaporized gas from said container; and means for circulating air to becooled adjacent the said container.

3. A refrigerator using solidified gas as a refrigerant comprising: ametal container for the said solidied gas; a shelf within the saidcontainer to support the said solidified gas, said shelf having openingsthrough it to permit passage of vaporized gas; heat insulating materialpartially lining the inside surfaces of the said container arranged insections to be removable to change the degree of insulating effect;hollow legs formed in the lower portion of said container; means forventing vaporized gas from the container; and means for' circulating airto be cooled, adjacent said container.

4. A refrigerator using solidified gas as a refrigerant comprising: ametal container for the said solidified gas, of a size and shape to gointo a standard refrigerator car ice bunker, through the ice hatchwayand fit, adjacent its upperetremity, into the tapered hatchway opening;means for supporting the said solidified gas'in said container; meansfor variably heat insulating the interior surfaces of said container;means for venting vaporized gas from said container; and hollow legsformed in the lower part of the said container.

SAMUEL T. SHERRICK.

